Followers

Tuesday, October 28, 2008

Scientists grow eggs from five-year-old girls

Children and young people who go through cancer are often left infertile by the treatment and are faced with having to use donated eggs and sperm or adopting to have their own family.

The problem is especially difficult for children who develop cancer before they reach puberty because they cannot freeze their own eggs and sperm.

But now scientists have managed to grow eggs in the laboratory from samples of ovarian tissue taken from girls as young as five.

Immature eggs can be removed from the tissue and grown to maturity in special culture.

The next step will be to see if they can be fertilised to create viable embryos. These could then be frozen and stored for future use or the unfertilised eggs could be frozen using the latest techniques which have proven more effective.

Between 1,500 and 1,700 children under the age of 15 are diagnosed with cancer each year and half of those are under the age of five.

The most common form of cancer in children is leukaemia, which affects 35 per cent, followed by brain or spinal tumours.

Research published online in the journal Fertility and Sterility revealed that a team at Hadassah Hebrew University Medical Centre in Jerusalem examined the ability to remove and preserve ovarian tissue from young female cancer patients and then retrieve, mature and freeze eggs from that tissue.

They worked with 19 patients between the ages of five and 20. On average they were able to retrieve an average of nine eggs per patient and 34 per cent of them were successfully matured.

"As our ability to treat childhood cancers improves, it becomes more important that those survivors are able to live rich, full lives, including the ability have children," said David Adamson, MD, President of the American Society for Reproductive Medicine.

"This research helps move us to the goal of allowing paediatric cancer survivors to become parents." Fertility doctors have attempted several methods to help young people going through cancer to conceive their own children.

Ovarian tissue has been successfully removed, frozen and reimplanted after the cancer treatment is complete. Some women have had babies through IVF and naturally after using this method.

Fertility specialists in the UK have also looked at developing a treatment to grow eggs from non-cancer sufferers, to allow them to delay motherhood.

The first stage of the technique involves removing slivers of ovarian tissue through keyhole surgery. Although only a few millimetres wide, each sample would contain thousands of immature eggs.

The procedure, which has been criticised by the pro-life charity Life, is seen as a low risk to women and has the added benefit of securing thousands of eggs rather than just a few.

It can then be stored until a woman is ready to try for a baby. The procedure is expected to be offered to patients within five years.